#include <QtGui>

#include "scribblearea.h"

ScribbleArea::ScribbleArea(QWidget *parent)
    : QWidget(parent)
{
    setAttribute(Qt::WA_StaticContents);
    modified = false;
    scribbling = false;
    myPenWidth = 2;
    myPenColor = Qt::black;
}

bool ScribbleArea::openImage(const QString &fileName)
{
    QImage loadedImage;
    if (!loadedImage.load(fileName))
        return false;

    QSize newSize = loadedImage.size().expandedTo(size());
    resizeImage(&loadedImage, newSize);
    canvasImage = loadedImage;
    modified = false;
    update();
    return true;
}

bool ScribbleArea::saveImage(const QString &fileName, const char *fileFormat)
{
    bool success = false;

    QImage visibleImage = canvasImage;
    resizeImage(&visibleImage, size());

    if(visibleImage.save(fileName, fileFormat))
    {
        modified = false;
        success = true;
    }

    return success;
}

bool ScribbleArea::saveImage(QByteArray &ba, const char *fileFormat)
{
    bool success = false;

    QBuffer buffer(&ba);

    if(buffer.open(QIODevice::WriteOnly))
    {
        QImage visibleImage = canvasImage;
        resizeImage(&visibleImage, size());

        if(visibleImage.save(&buffer, fileFormat))
        {
            modified = false;
            success = true;
        }
    }

    return success;
}

void ScribbleArea::setPenColor(const QColor &newColor)
{
    myPenColor = newColor;
}

void ScribbleArea::setPenWidth(int newWidth)
{
    myPenWidth = newWidth;
}

QImage ScribbleArea::image() const
{
    QImage visibleImage = canvasImage;
    resizeImage(&visibleImage, size());

    return visibleImage;
}

void ScribbleArea::clear()
{
    canvasImage.fill(qRgb(255, 255, 255));
    modified = false;
    update();
}

void ScribbleArea::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton)
    {
        lastPoint = event->pos();
        scribbling = true;
    }
}

void ScribbleArea::mouseMoveEvent(QMouseEvent *event)
{
    if ((event->buttons() & Qt::LeftButton) && scribbling)
        drawLineTo(event->pos());
}

void ScribbleArea::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton && scribbling)
    {
        drawLineTo(event->pos());
        scribbling = false;
    }
}

void ScribbleArea::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    QRect dirtyRect = event->rect();
    painter.drawImage(dirtyRect, canvasImage, dirtyRect);
}

void ScribbleArea::resizeEvent(QResizeEvent *event)
{
    if (width() > canvasImage.width() || height() > canvasImage.height())
    {
        int newWidth = qMax(width() + 128, canvasImage.width());
        int newHeight = qMax(height() + 128, canvasImage.height());
        resizeImage(&canvasImage, QSize(newWidth, newHeight));
        update();
    }
    QWidget::resizeEvent(event);
}

void ScribbleArea::drawLineTo(const QPoint &endPoint)
{
    QPainter painter(&canvasImage);
    painter.setPen(QPen(myPenColor, myPenWidth, Qt::SolidLine, Qt::RoundCap,
                        Qt::RoundJoin));
    painter.drawLine(lastPoint, endPoint);
    modified = true;

    int rad = (myPenWidth / 2) + 2;
    update(QRect(lastPoint, endPoint).normalized()
                                     .adjusted(-rad, -rad, +rad, +rad));
    lastPoint = endPoint;
}

void ScribbleArea::resizeImage(QImage *image, const QSize &newSize) const
{
    if (image->size() == newSize)
        return;

    QImage newImage(newSize, QImage::Format_RGB32);
    newImage.fill(qRgb(255, 255, 255));
    QPainter painter(&newImage);
    painter.drawImage(QPoint(0, 0), *image);
    *image = newImage;
}

void ScribbleArea::print()
{
#ifndef QT_NO_PRINTER
    QPrinter printer(QPrinter::HighResolution);
 
    QPrintDialog *printDialog = new QPrintDialog(&printer, this);
    if (printDialog->exec() == QDialog::Accepted)
    {
        QPainter painter(&printer);
        QRect rect = painter.viewport();
        QSize size = canvasImage.size();
        size.scale(rect.size(), Qt::KeepAspectRatio);
        painter.setViewport(rect.x(), rect.y(), size.width(), size.height());
        painter.setWindow(canvasImage.rect());
        painter.drawImage(0, 0, canvasImage);
    }
#endif // QT_NO_PRINTER
}
